feat(orbit): per-guest suggestion mute + global pending-cap setting

Two anti-spam knobs the host can dial during a live session:

1. Per-guest suggestion mute — Mic / MicOff toggle next to the
   kick/ban buttons in the participants popover. Symmetric (re-enable
   later). State lives in OrbitState.suggestionBlocked: string[]; the
   guest reads it and disables its own Suggest controls so the user
   sees a clear "muted" state instead of silent failures. Host-side
   sweep also drops their outbox entries as a safety net.

2. Max pending approvals cap — number input in the session-settings
   popover, default 0 (= unlimited so existing sessions are unaffected).
   When set, the host sweep stops folding new outbox entries into the
   approval list once the cap is reached. The OrbitQueueHead surfaces
   "X / Y pending" so guests can see when they're getting close.

State changes are additive on the wire — both fields are optional, with
parseOrbitState defaulting them, so older clients keep working.

evaluateOrbitSuggestGate() centralises the guest-side allow/block check
shared between useOrbitSongRowBehavior and the ContextMenu Add-to-Session
items, plus suggestOrbitTrack as a defensive last line.

i18n: en + de + fr + nl + zh + nb + ru + es.

Also fixes an earlier dedupe-key collision: the (user, trackId) cache
keys were missing their separator (NULL byte slipped in during the
previous patch), so two tracks could share a key and one of them
silently overwrite the other. Restored the space separator.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/hooks/useOrbitHost.ts

@@ -87,7 +87,12 @@ export function useOrbitHost(): void {
       let afterSweep = base;
       try {
         const snaps = await sweepGuestOutboxes(base.sid, base.host);
-        afterSweep = applyOutboxSnapshotsToState(base, snaps);
+        // Hand the cap-check the host's local merged/declined sets so it can
+        // tell which `state.queue` items are still actually awaiting approval.
+        afterSweep = applyOutboxSnapshotsToState(base, snaps, Date.now(), {
+          mergedKeys: new Set(store.mergedSuggestionKeys),
+          declinedKeys: new Set(store.declinedSuggestionKeys),
+        });
       } catch { /* best-effort; keep old participants and queue */ }
 
       // 2) Merge newly-suggested items into the host's local play queue so